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34 S o f t w a r e & S y s t e m s R e q u i r e m e n t s E n g i n e e r i n g : I n P r a c t i c e

2.6 Dynamic Tailoring of an Artifact Model
Software projects come in different sizes and use different
methodologies. Large plan-driven projects can take years to
implement and have staffs of well over 100 developers. Small, agile
projects might have just two or three developers, and the project
duration could be as short as a week or two. When creating a REAM
for a project, clearly one size does not fit all. If an organization has a
range of projects on an ongoing basis, it is a good practice to provide
some built-in tailoring facilities. An artifact, for example, could be
mandatory on a “large” project, optional on a “medium-sized”
project, and not used at all on a “small” project. If the project artifacts
are tagged during the creation of the artifact model, it then becomes
possible to filter and present the required information, or to couple it
to a workflow used to reinforce the process. Tailoring techniques
range from simple manual selection of artifacts to very sophisticated
approaches such as the use of neural nets [Park et al. 2006]. Regardless
of the tailoring approach, it will not work unless the artifacts in the
model have attributes that permit them to be evaluated based on
type, size, and duration of the project. An example of a small model
used to define the artifacts for a prototyping effort can be seen in
Figure 2.14. An example table fragment for defining tailoring rules is
shown in Figure 2.15.

2.7 Organizational Artifact Model Tailoring
In addition to the tailoring of an artifact model for a specific project,
high-level organizational models can be used as the starting point
for the creation of project-specific models. An example is given in
Figure 2.16. The starting point was a corporate-level model defining
the core artifacts needed on any project. That model is then modified
for the specific organization within the company, and finally the
model is completed on a per-project basis.

Used to
identify Shown in
Business Goal Feature Prototype
1..* 1..* 1..* 1

Shown to
1..*
* *
Stakeholder Request Customer
May provide
feedback as
FIGURE 2.14 Artifact model for small prototyping project